1. Field of the Invention
This invention relates to systems for cleaning the magnetic read, write and erase heads of cartridge tape drives and more particularly to tape drives and cartridge tape drives of the type referred to as "streamer" or "streaming" mode and "start-stop" mode drives. Streamer and start-stop drives are typically used as backup data storage for disc drive systems. As with other pieces of data processing equipment, streamer and start-stop drives and other cartridge tape drives require preventive care and periodic maintenance to ensure efficient, smooth and error free operation. Delicate magnetic read, write and erase heads and the tape scraper which are usually found on this equipment must be periodically cleaned, but the cleaning method must not damage the heads. This invention provides a safe, efficient and simple method of simultaneously cleaning all the magnetic heads and the adjacent tape scraper of the tape drive.
2. Description of the Prior Art
Streamer and start-stop drives are a relatively recent development and head cleaner systems for them have not been produced. However, head cleaning devices have been developed for audio cassette and audio cartridge systems.
Audio tape cleaning devices are generally designed to clean only the play head, leaving the other heads of the audio system untouched. The ability to clean all of the heads in computer tape drives is necessary to prevent faulty reading, writing or erasing of information. Such errors could lead to incorrect output data or the failure of the entire computer system that is using the tape drive for storage.
Various cartridge and cassette cleaners are disclosed in U.S. Pat. Nos. 4,141,053 to Kara, 4,149,206 to Loiselle, 4,225,893 to Loiselle, 4,272,796 to Van Kreuningen et. al., 3,761,994 to Becht, 3,783,470 to Myers et. al., and 3,955,214 to Post et. al. Most of these devices use a horizontally pivoting cleaning arm or a rotating pulley and a cleaning pad that is attached to the arm or pulley. The Myers system imparts a sliding motion to a cleaning pad. Thus, these devices use a motion that is parallel to the tape path for the cleaning action and are designed to clean only one magnetic head. Furthermore, this parallel cleaning motion has been found to be ineffective for removing dirt from the corners of the magnetic heads.
U.S. Pat. No. 4,272,796 to Van Kreuningen, et al., discloses a cleaning system which uses a combination of a vertical and a horizontal cleaning motion. This system is also designed to clean only one magnetic head at a time.
The patents issued to Post et. al., Kara, Loiselle and to Van Kreuningen, et. al. are designed to use the transport mechanism of the audio cassette deck to provide the motion of the cleaning pad. Therefore, these designs produce a rapid scrubbing motion across the head. This results in repeated rubbing of the play head. Although this motion should not damage the magnetic heads of a cassette unit, such repeated cleanings could damage the more delicate magnetic heads of computer tape drives. Furthermore, these audio cleaning systems require that power be applied to the cassette deck. It is not always desirable to have power applied to computer tape drives while cleaning their heads.
The cleaning system disclosed in U.S. Pat. No. 4,158,871, to Leaming, which is used for cleaning audio tape cartridge playback units, uses a shaft with a cotton swab or felt pad attached to the end of the shaft. The cartridge is inserted into the playback unit so the pad or swab may be rubbed against the playing head. If too much force is applied to the shaft, the magnetic heads may be damaged.
Other prior art systems use abrasive cleaning pads or belts to rub the playing head to remove accumulated dirt. Repeated usage of abrasive pads or belts can cause damage to the magnetic heads.
It is therefore the object of the present invention to provide a system for simultaneously cleaning all of the heads and the scraper of a cartridge tape drive system without any need for disassembly of the machine.
It is another object of the present invention to provide a head cleaning system which is substantially nonabrasive and ensures that excessive force cannot be applied to the head assembly and thus prevents possible damage to the individual read, write and erase heads.
It is an object of this invention to provide a head cleaning system which does not require that power be applied to the tape drive during the cleaning procedure.
It is a further object of this invention to provide a head cleaning system which uses the drive mechanism of the tape drive to impart the motion to the cleaning pad.